@Dharmendra Kumar-FT Thank you for reaching out to us!
I see that you are planning for DR for your SAP systems and wanting to reserve IP addresses during failover. It is possible to retain IP address (Private IP addressing) in the target region identical to the source region. The private IP is replicated within the target region the same as the source. Ref doc: https://zcusa.951200.xyz/en-us/azure/site-recovery/site-recovery-retain-ip-azure-vm-failover
However, the Public IPs are not transferrable. A new region would require a new Public IP. Workloads brought up as part of failover process must be assigned an Azure Public IP resource available in the target region.
Reference URL - https://zcusa.951200.xyz/en-us/azure/site-recovery/concepts-public-ip-address-with-site-recovery#public-ip-address-assignment-using-recovery-plan
You can look at introducing Traffic manager which will handle the region based traffic shift by keeping the URL same. For more detail refer to "Public endpoint switching with DNS level Routing" and failover scenarios with Traffic Manager section.
Hope this helps!
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